Conservative MP Zac Goldsmith has secured the debate in the House of Commons to end fishing discards, which result in half the fish caught in the North Sea being unnecessarily thrown back either dead or dying.

At the end of the debate on Thursday, MPs will be asked to vote for a motion calling on the government to vote against a reformed EU common fisheries policy unless it ends the scandal of discarded fish. If passed, the motion will also enable the UK to impose its own standards on all vessels fishing within the 12-mile limits of its territorial waters, regardless of their country of origin. The motion also calls for a regulatory system that distinguishes between small fishing vessels and mega-trawlers.

Earlier in the year, Goldsmith tabled an early day motion in parliament demanding an end to discards. A total of 240 MPs signed it, making it the second most supported EDM since the last election. Support is cross-party, with signatures from members of the Conservative, Labour, Democratic Unionist, Scottish National, Green and Social Democratic and Labour parties, the Liberal Democrats, Plaid Cymru and others.

Zac Goldsmith said: "It is hugely encouraging that 240 MPs, including more than 100 coalition MPs, have signed the EDM to end the crazy practice of discarding fish. This… has also been condemned by the prime minister and the fisheries minister. Plainly, there is a clear appetite for a radical shift, and I hope this will translate into votes for the motion. This is our chance to put an end to fish discards and to restore balance in our territorial waters."

The move by Goldsmith follows public anger at the practice of discarding fish, which was highlighted in Channel 4's Fish Fight series – led by chef and food writer Hugh Fearnley-Whittingstall – which has prompted hundreds of thousands of people to sign a petition calling for reform.

Fearnley-Whittingstall said: "It's fantastic news that Zac Goldsmith's motion on discards and CFP reform is going to be properly debated in parliament on Thursday. Of course, I'm hoping the motion will be carried by a massive majority. If so, it will give real impetus and credibility to Britain's leading role in securing much-needed reform of a broken European fisheries policy. In particular, it will be a vital step towards ending the madness of discards, and securing a sustainable future for our fisheries."

Discarding results in as much as two-thirds of the fish caught being thrown back into the water, usually dead. About 1m tonnes are estimated to be thrown back each year in the North Sea alone.